The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 21, 2012
Filed:
Sep. 02, 2008
Applicant:
Tadashi Maeda, Tokyo, JP;
Inventor:
Tadashi Maeda, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R 25/00 (2006.01); H03D 13/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A phase comparator is provided that solves the problem that a VCO cannot be controlled with high precision. A frequency divider frequency-divides a VCO signal applied as input to an input terminal () in steps, and supplies the VCO signals of each step as output. A latch unit latches the VCO signal that is applied to the input terminal () and each VCO signal that was supplied from the frequency divider based on a reference signal that is applied to an input terminal (). An output unit supplies the latch results realized by the latch unit as phase difference signals that indicate phase differences of the reference signal and the VCO signals.